Oldest known lizard fossil pushes group's origins back 75 million years

[Judi Lynn]

CT scan reveals identity of ancient remains found years ago in the Italian Alps
BY SUSAN MILIUS 4:24 PM, MAY 30, 2018

A little animal that washed out to sea 240 million years ago off the coast of what’s now Italy turns out to be the oldest known fossil of a lizard.

The identification pushes back the fossil record of snakes and lizards by about 75 million years, says Tiago Simões of the University of Alberta in Edmonton, Canada. He and colleagues used observations of the fossil, called Megachirella wachtleri, and of related living and extinct species plus genetic data to reconstruct the evolutionary history of squamates, the reptile group that today includes snakes and lizards, the researchers report in the May 31 Nature.

“Understanding lizard and snake evolution has been a constant problem in paleontology,” says vertebrate paleontologist Stephanie Pierce of Harvard University who worked on the issue years ago but wasn’t involved in the new study. The trouble comes largely from a lack of relevant fossils, she says. That dearth isn’t just because little animals don’t fossilize as readily as big ones do. “Things like giant dinosaurs — they’re pretty easy to spot,” she says. “But if you’re looking for something that can fit in the palm of your hand, that makes it very challenging.”

A collector found M. wachtleri almost 20 years ago in a part of the Italian Alps that had once been underwater. But researchers didn’t categorize it as a full member of the squamate branch of reptiles, until now. The sole specimen is partly embedded in rock, which obscured some of the creature’s telltale features. Now a CT scan has revealed previously unknown squamate details of its palate, braincase, limbs and shoulder, Simões says.

More:
https://www.sciencenews.org/article/oldest-known-lizard-fossil-pushes-origins-back-75-million-years?utm_source=editorspicks060318&utm_medium=email&utm_campaign=Editors_Picks

[Judi Lynn]

1. Scientists find the 240-million-year-old 'mother of all lizards'

SARAH KAPLAN
Last updated 05:00, June 4 2018

Here's a fact you should know about the world in which you live: It's home to more kinds of scaly reptiles than all the mammal families combined.

The reptile order Squamata​ – which includes snakes, lizards and New Zealand species such as geckos and skinks – is the largest order of living land vertebrates on the planet.

And yet scientists know surprisingly little about where all those geckos and vipers and iguanas and skinks came from. Genetic evidence suggests the order originated in the Permian​ period, more than 250 million years ago. But the oldest known squamate fossil was about 70 million years younger than that.

"That's more time than there is between us and the dinosaurs, and we had no clue what was going on," said Tiago Simoes, a palaeontologist at the University of Alberta.

More:
https://www.stuff.co.nz/science/104362593/.html